Bilingual Engineers: Why English Fluency in Costa Rica Wins

Every nearshore agency on the internet says their engineers speak English. We do too. The difference is whether the engineer on your standup tomorrow can argue a tradeoff with your VP of Engineering without flinching, or whether they nod, write down what they think you said, and ship the wrong thing.

This is the founder-to-founder version: what fluent actually means at standup, how Costa Rica got here, how we screen, and where language alone is not enough.

CEFR levels and what they mean at standup

The CEFR scale (A1 through C2) is the European reference everyone in language testing uses. Our internal shorthand:

• B1. Can read tickets and ship code from written specs. Will freeze on a live architecture call. Fine for an offshore-style ticket queue, not for an embedded role.
• B2. Can do a daily standup, ask clarifying questions in writing, follow a Zoom meeting that does not go off the rails. Will struggle with sarcasm, fast cross-talk, or a hostile customer call.
• C1. Can lead a sprint planning, push back on a PM, explain a tricky migration to a stakeholder who is not technical. This is the level where the language stops being a tax on your team.
• C2. Indistinguishable from a strong non-native speaker in a US office. Rare. We do not promise C2.

What you should hire for at the senior level is solid B2 minimum, ideally C1. Anything below B2 in speech and you are paying a productivity tax every meeting.

Why Costa Rica is good at this

Three things stacked on top of each other.

First, the public school system has taught English from grade 1 for over twenty years. Uneven, but the floor is higher than most of LATAM.

Second, the call-center industry. From the late 90s onward, Costa Rica became the back office for US customer support: Amazon, HP, Sykes, Convergys, Concentrix. A generation got paid to talk to angry Americans eight hours a day. Many went to night school for software afterward, or their kids did. That is where a lot of our engineering English actually comes from. Not classroom English. People who learned to handle a stressed US customer at 2pm on a Tuesday.

Third, proximity. Most senior engineers we work with have been on US client calls for years through a previous BPO or agency job, or have lived in the US for a stretch. Accent is mild, idioms are familiar.

If you want the longer version of the Costa Rica case, we wrote why Costa Rica for nearshore and the decision framework earlier in the year.

The resume-English trap

Here is what burns most US founders who hire direct: people overstate English on the resume. Someone writes “C1 - Advanced” because their reading is solid and they passed a written test in college. Get them on a live call and they are a strong B1 in speech, maybe weak B2.

Written English and spoken English are different muscles. Costa Rican engineers tend to read well above their speaking level because they consume technical content in English daily. That confidence does not always survive a live call. Written tests do not work. You have to talk to them.

How we screen

Three steps, every candidate, no exceptions.

Live conversation, 20 minutes, unstructured. Not “tell me about yourself”. We ask them about a recent project and let them run. We are listening for whether they can self-correct, ask back for clarification, handle a follow-up that goes off the script. If they freeze when we change the subject, that is a flag.

Technical explanation under light pressure. We ask them to whiteboard or screen-share something real from their last role. The goal is to see them switch between concept-level English (“we needed to denormalize because the join cost was eating us”) and detail-level English (“I added a composite index on tenant_id and created_at”). Both registers have to work.

Async writing sample. A short Loom or written reply to a fake Slack thread we send them. This catches the inverse problem: engineers whose speech is fine but who write in a way that needs a human translator before a US PM can act on it.

After those three, we have a sharp read. The vast majority of seniors we present land at solid B2 to mid C1 in speech and strong C1 in writing. We tell you the level on the profile. We do not round up.

Where it matters most

English fluency is a tax on every meeting, but the tax is not flat. It hits hardest in:

• Product conversations. Nuance, hedging, “I think we should consider” versus “we should”. A B1 speaker flattens all of that.
• Customer-facing roles. Solutions engineers, support escalations, anyone who talks to your users.
• Async documentation. A senior who writes ambiguous Slack messages costs your team hours per week.
• Disagreement. This is the underrated one. A senior engineer has to push back. If language friction makes them nod instead of object, you lose the value of seniority.

For pure feature work behind a clear ticket queue, B2 reading and B1 speech is workable. For anything embedded in your team, hire C1 or call it a different model. That is the same logic we cover in outsourcing vs outstaffing and the upcoming key benefits of Costa Rica staff augmentation.

When language is not enough

This is the part most agencies leave out. A C1 speaker can still ship the wrong thing if the cultural translation is off.

A few examples we have seen.

Direct feedback. US engineering culture rewards “this is wrong because”. Costa Rican culture, by default, softens disagreement. A C1 speaker who has not been around US teams will still phrase a hard objection as a question, and you will miss the signal. We coach for this on every new placement.

Async-vs-sync expectations. A US founder who Slacks “are we on track?” at 4pm and gets no answer until 9am the next day assumes the worst. A CR engineer who treats Slack as async thinks nothing of it. Both are right by their own norms. Someone has to set the rule on day one.

We talk about all of this in the first-week onboarding. It is the difference between a placement that lands and one that drifts.

If you want the broader picture of why Costa Rica plus the rest of LATAM is a serious talent base, we cover that in our pillar on technical staff augmentation and on our why Costa Rica page.

Judge the English yourself

You should not take our word for any of this. Get on a call with one of our engineers and decide for yourself in twenty minutes.

WhatsApp us, usually answered within an hour.